Figure 2. Retention of ball-and-sockets (BSs) at 3 weeks. A: Wild-type (WT) sample showing BSs (arrowheads) as connexin 46 (Cx46)-enriched areas where one fiber has invaginated into a neighboring fiber. Small Cx46 gap junction (GJ) plaques (arrows) appeared on the long and narrow sides of fibers outside of the BSs. B: Most regions of knock-in (Ki) fiber sections showed few to no structures resembling BSs, but many large Cx46 GJ plaques are apparent (arrows). C: Some limited regions still appeared to have Cx46-enriched BS structures (arrowheads). Scale bar: 5 μm.